There is a body of literature which discloses a variety of natural and synthetic pyrroles as antifungal and antibacterial agents. However, this literature appears to be devoid of any disclosure or suggestion that would lead one to believe that pyrrole carbonitriles and/or nitropyrroles could be effectively employed for the control of insects, acarids or mollusks, or for the protection of plants or crops from attack by these pests.
2,3-Dichloro-4-nitropyrrole is disclosed and its antibiotic effectiveness described in U.S. Pat. No. 4,376,778. The publication, Journal of Antibiotics 34, (12): 1569 (1981) likewise describes the antibiotic activity of this compound and several other mono- and dichloro-3-nitropyrroles, including a 2,4,5-trichloro-3-nitropyrrole; however, no reference is made to any insecticidal, scaricidal or molluscicidal activity observed or indicated for such compounds. U.S. Pat. No. 4,563,472 discloses generically a series of compounds illustrated by the structure: ##STR1## where E is a 2,3,3-triiodoallyl group or a 3-iodopropargyl group; A, B, C and D each individually represent a nitrogen atom or a carbon atom, and X, Y and Z may be a hydrogen atom, chlorine atom, or a nitro group. These compounds have antifungal activity.
4,5-Dihalopyrrole-2-carbonitrile (Br and Cl) and their herbicidal properties are disclosed in U.S. Pat. No. 3,985,539. Certain nitropyrroles, dinitropyrroles, cyanonitropyrroles, and cyanodinitro-pyrroles, which include N-substitution by methyl, propyl, or hydroxyethyl groups, have been examined as radiosensitizers.
It is an object of the present invention to provide certain novel pyrrole carbonitrile and nitropyrrole compounds that are highly effective for controlling insects, acarina and mollusks. It is also an object of the invention to protect growing plants and crops from attack by insects, acarina and mollusks, by contacting said pests, or their food supply, breeding grounds or habitat with an insecticidally, acaricidally or molluscicidally effective amount of a pyrrole carbonitrile or nitropyrrole.
These and other objectives of the invention will become more apparent from the detailed description thereof set forth below.